Fluid pump for delivering a fluid

ABSTRACT

A fluid pump for delivering a fluid of a cooling system is disclosed. The fluid pump includes a pump housing surrounding a pump housing interior on which a fluid inlet for introducing the fluid into the pump housing interior and a fluid outlet for discharging the fluid out of the pump housing interior are disposed. A delivery unit is arranged in the pump housing interior for driving the fluid introduced into the pump housing interior. An electric motor is arranged in the pump housing interior for driving the delivery unit. A control device is arranged outside the pump housing and comprises power electronics. The control device is electrically connected to the electric motor for controlling the electric motor.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to German Application No. DE 10 2021 208 474.5 filed on Aug. 4, 2021, the contents of which are hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The invention relates to a fluid pump for delivering a fluid, in particular in a fluid path of a cooling system, and to a cooling system having such a fluid pump.

BACKGROUND

Fluid pumps are often employed in cooling systems in order to deliver a fluid functioning as cooling medium. Because of the installation space that is often limited in particular in motor vehicles, such fluid pumps are to be embodied so as to be as compact as possible. In doing so it proves to be problematic however that the electrical components of the fluid pump generate waste heat during the operation, which especially with a compact design, can be discharged from the fluid pump only with relative difficulty.

It is therefore an object of the present invention to create an improved embodiment for a fluid pump which is characterised in particular by an improved heat discharge with low installation space requirement at the same time.

This object is solved through the subject of the independent patent claim(s). Preferred embodiments are subject of the dependent patent claims.

SUMMARY

Accordingly, the basic idea of the invention is to arrange a control device of the fluid pump, whose power electronics generate waste heat during the operation, outside the pump housing and electrically connect the same with an electric motor arranged within the pump housing for driving the fluid pump. In this way, the installation space needed within the fluid pump can be reduced. Since the control device generating the waste heat is arranged outside the pump housing, only little waste heat is incurred within the pump housing. Thus, no special measures whatsoever for discharging the said waste heat have to be taken for the electric motor and for the delivery unit. Consequently, no or only little installation space for heat discharge measures is needed within the pump housing either. The control device, by contrast, can be positioned outside the pump housing in a place—in particular spaced apart from the pump housing—in which discharging the waste heat generated by the power electronics is easily and effectively possible. By way of the electrical connection provided between the electric motor and the power electronics it is ensured that the electric motor can be electrically energised by the power electronics for driving the delivery unit and thus for delivering the fluid. The fluid pump according to the invention presented here can therefore be installed in a cooling system in a flexible and installation space-saving manner. There it proves to be particularly advantageous that the pump housing with the delivery unit and with the electric motor on the one hand and the control device with the power electronics on the other hand can be arranged spatially separated from one another in different positions of the cooling system.

A fluid pump according to the invention serves for delivering a fluid, in particular in a fluid path. The fluid can function as cooling medium. The fluid pump includes a pump housing, which surrounds a pump housing interior. On the pump housing, a fluid inlet for introducing the fluid into the pump housing interior and a fluid outlet for discharging the fluid from the pump housing interior are formed. Apart from this, a delivery unit for driving the fluid introduced into the pump housing interior is arranged in the pump housing interior. The delivery unit can comprise a rotatable drive shaft with delivering blades for transporting the fluid. The drive shaft can be rotatably mounted on the pump housing. Apart from this, an electric motor for driving the delivery unit is arranged in the pump housing interior. The electric motor can be a three-phase BLDC motor. The electric motor can be drive-connected to the drive shaft of the delivery unit. Outside the pump housing, a control device of the fluid pump is arranged. The control device includes power electronics which, for controlling the electric motor, are electrically connected with the electric motor. The power electronics can include for example power transistors—for example MOSFETs—for electrically energising the electric motor, which generate waste heat during the operation of the electric motor. The power electronics can comprise further electrical and electronic components for controlling the power transistors. These components can also generate waste head during the operation. The mentioned components can be arranged on a circuit board.

According to a preferred embodiment, the control device is arranged spaced apart from the pump housing and electrically connected with the electric motor by means of an electrical connection. In this way, the control device and the pump housing can be installed in different positions in a cooling system. It is possible, in particular, to place the control device so that the waste heat generated by the power electronics can be effectively discharged. For this purpose it is conceivable in particular to position the control device so that it is thermally coupled to a fluid path through which a fluid functioning as cooling medium flows. In this case, the waste heat generated by the control device can be absorbed by the cooling medium or fluid and transported away. The fluid or cooling medium can be that fluid which is delivered by the fluid pump. In this case, the fluid path thermally coupled to the control device can be that fluid path in which the fluid pump is arranged. However, different fluids or fluid paths can be used alternatively to this. In this case, the fluid path which is thermally coupled to the control device is thus distinct from that fluid path in which the fluid pump is arranged. Consequently, the fluid absorbing the waste heat from the control device is also distinct from that fluid which is delivered by the fluid pump.

According to an advantageous further development, the control device includes a housing formed separately from the pump housing. The housing surrounds a housing interior in which the power electronics are arranged. In this way, the power electronics can be protected from damage or even destruction. In addition to this, the control device can be installed independently from the pump housing spaced apart from the same.

Particularly preferably, the housing of the control device is thus arranged spaced apart from the pump housing. This makes possible arranging the pump housing with the delivery unit and with the electric motor directly in the fluid path. Compared with this, the control device with the power electronics generating the waste heat can be arranged in a position spaced apart from the fluid path, in which the generated waste heat can be particularly effectively discharged.

Practically, a housing material of the housing of the control device is a metal at least in regions. Since metals generally have a high heat conductivity, this facilitates discharging the waste heat generated by the power electronics from the housing interior to the outside.

According to a preferred embodiment of the invention, an electrical feedthrough each can be provided on the pump housing and on the housing of the control device. By way of these feedthroughs an electrical connection is fed through between the electric motor and the power electronics. Accordingly, the required electrical connection between the electric motor arranged in the pumps housing and the power electronics arranged in the housing of the control device can be realised in a simple manner.

According to an advantageous further development, the electrical connection comprises at least two electrical supply lines. Preferably, four electrical supply lines can be provided. Thus, both a direct current motor and also a three-phase BDLC motor can be supplied with electric energy in order to drive the rotor of the electric motor and thus also the delivery unit drive-connected to the electric motor.

According to another advantageous further development, the electrical connection includes an electrical shield, in particular an electrical shielding line. In this way, coupling electrical interference signals into the electrical supply lines can be avoided or such a coupling-in at least counteracted.

Preferably, the pump housing can be formed in one piece. This variant can be produced particularly easily. Apart from this, it is avoided compared with a two- or multi-part design of the pump housing that fluid, because of leakages, can leak out of the pump housing interior into the external environment of the pump housing. Providing seals between the individual housing parts can also be dispensed with. This in turn is accompanied by cost advantages in producing the pump housing.

According to a preferred embodiment, the one-piece pump housing is formed from at least two housing parts. The at least two housing parts are each non-detachably connected to one another by means of a firmly bonded connection. Thus, the components of the fluid pump to be placed in the pump housing, i.e. in particular the delivery unit and the electric motor, can be placed in the housing interior during the course of the assembly and subsequently the housing parts surrounding the housing interior joined to one another in a firmly bonded manner. This simplified the assembly of the fluid pump compared with conventional multi-part fluid pumps to a considerable extent.

According to a preferred embodiment, the one-piece pump housing includes a pump housing flange for mounting the pump housing to an external cooling system. The pump housing flange in this embodiment projects radially to the outside away from a circumferential wall of the pump housing and is integrally formed on the circumferential wall. Thus, the fluid pump can be easily fastened to a component of the cooling system.

Since the component arranged in the pump housing interior do not generate any or only relatively little waste heat it is not absolutely necessary for the heat discharge to use as housing material a metal with a high heat conductivity. Practically, the material of the pump housing can therefore be a plastic or include a plastic. This measure leads to reduced costs in producing the fluid pump.

Further, the invention relates to a cooling system. The cooling system according to the invention includes a fluid path through which a cooling medium can flow. In the fluid path, a fluid pump according to the invention introduced above for delivering the cooling medium is arranged. The advantages of the fluid pump according to the invention explained above therefore apply also to the cooling system according to the invention. The cooling system can include further components arranged in the fluid path for influencing the fluid such as for example a heat exchanger, a filter device and a valve device and the like. The control device of the fluid pump with the cooling system according to the invention is arranged spaced apart from the pump housing and thermally coupled to the fluid path, so that waste heat generated by the control device during the operation can be passed on to the cooling medium delivered through the fluid path.

According to a preferred embodiment of the cooling system, the fluid path is delimited by a tubular body on which the control device is arranged. Particularly, preferably, the housing of the control device can be fastened to the tubular body. Thus, the fluid flowing through the fluid path can function as cooling medium which can absorb the waste heat generated by the power electronics.

According to an advantageous further development of the cooling system, the cooling system comprises a modular flange on which the fluid pump, preferentially with its pump housing flange, is fastened. This facilitates mounting the fluid pump on the cooling system.

Further important features and advantages of the invention are obtained from the subclaims, from the drawings and from the associated figure description by way of the drawings.

It is to be understood that the features mentioned above and still to be explained in the following cannot only be used in the respective combination stated but also in other combinations or by themselves without leaving the scope of the present invention.

Preferred exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein same reference numbers relate to same of similar or functionally same components.

BRIEF DESCRIPTION OF THE DRAWINGS

It shows, in each case schematically:

FIG. 1 a rough schematic representation of a cooling system according to the invention,

FIG. 2 the fluid pump of the cooling system of FIG. 1 in a separate perspective representation.

DETAILED DESCRIPTION

FIG. 1 illustrates in a schematic representation an example of a cooling system 20 according to the invention having a fluid pump 1 according to the invention. The cooling system 20 includes a fluid path 21 that can be flowed through by a cooling medium K in the form of a fluid F. In the fluid path 21, the fluid pump 1 for delivering the fluid F is arranged. The fluid path 21 can be delimited for example by a tubular body 22. The fluid pump 1 includes a pump housing 2 which surrounds a pump housing interior 3.

For illustration, FIG. 2 shows the fluid pump 1 only shown schematically in FIG. 1 in a perspective representation. On the pump housing 2 a fluid inlet 4 a for introducing the fluid F into the pump housing interior 3 is formed on the front side and a fluid outlet 4 b (only noticeable in FIG. 1 , concealed in FIG. 2 ) is formed on the circumferential side for discharging the fluid F out of the pump housing interior 3. In the pump housing interior 3, a delivery unit 18 for driving the fluid F introduced into the pump housing interior 3 is provided. Further, an electric motor 19 for driving the delivery unit 18 is arranged in the pump housing interior 3. The electric motor 19 can be a three-phase motor. For controlling the movement of a rotor (not shown) of the electric motor 19 and for the electrical energising of the stator (not shown) of the electric motor 19 required for this purpose, an electrical control device 6 with power electronics 5 is present outside the pump housing 2. For controlling or electrically energising the electric motor 19, the control device 6, arranged spaced apart from the pump housing 2, is electrically connected to the electric motor 19 by means of an electrical connection 15.

As illustrated by FIG. 2 , the pump housing 2 can have a cylindrical geometrical shape. An axial direction A then extends along a centre longitudinal axis M of the cylindrical pump housing 2. A radial direction R extends perpendicularly to the axial direction A away from the centre longitudinal axis M. A circumferential direction U runs perpendicularly both to the axial direction A and also to the radial direction R round about the centre longitudinal axis M. In the exemplary scenario the pump housing 2 is formed in one piece. Here, the pump housing 2 is formed out of three housing parts 11 a, 11 b, 11 c, which are each non-detachably connected to one another by means of a firmly bonded connection 7 a, 7 b—for example a welded connection. The material of the pump housing 2 can be a plastic. The one-piece pump housing 2, as shown in the FIGS. 1 and 2 , can comprise a pump housing flange 8 for mounting the pump housing 2 to a modular flange 23 of the cooling system 20. According to FIG. 2 , the pump housing flange 8 can project from a circumferential wall 9 of the pump housing 2 radially to the outside and be integrally formed on the same. The circumferential wall 9 of the pump housing 2 extends along the circumferential direction U and completely encircles the centre longitudinal axis M. The pump housing flange 8, as shown in FIG. 2 , can comprise multiple projections 10 arranged spaced apart from one another along the circumferential direction U and projecting from the circumferential wall 9 radially to the outside, in each of which a through-opening 25 is arranged. The through-openings 25 can be used for screw connections. The cooling system 20 can comprise a modular flange 23 on which the fluid pump 1 can be fastened with the pump housing flange 8. By means of the pump housing flange 8, the fluid pump 1 can be screwed to the modular flange 23.

The control device 6 according to FIG. 1 includes a housing 12 formed separately from the pump housing 2, which surrounds a housing interior 14 (not shown in FIG. 2 ). The power electronics 5 are arranged in the housing interior 14 of the control device 6. As is further illustrated by FIG. 1 , the housing 12 of the control device 6 is arranged spaced apart from the pump housing 2. On the pump housing 2 and on the housing 12 of the control device 6, an electrical feedthrough 24 a, 24 b each is present. By way of the two feedthroughs 24 a, 24 b, an electrical connection 15 is fed through between the electric motor 19 and the power electronics 5. In the example, the electrical connection 15 includes four electrical supply lines 16 for electrically energising the coils of the stator (not shown) of the three-phase electric motor 19. The electrical connection 15 can additionally include an electrical shield 13 for shielding the supply lines 16, which in turn can comprise an electrical shielding line 17.

Since according to FIG. 1 the control device 6 of the fluid pump 1 is arranged spaced apart from the pump housing 2, the fluid pump 1 can be directly arranged on the tubular body 22 delimiting the fluid path 21. Because of this the power electronics 5 in turn can be thermally coupled to the fluid or cooling medium K conducted through the fluid path 21. In this way, the waste heat generated by the power electronics 5 is transferred to the fluid 5 as a result of which the power electronics 5 is cooled.

The housing material of the housing 12 of the control device 6 is a metal at least in regions. This applies in particular to that region of the housing 12 which lies against the tubular body 22. In this way, the thermal contact between the power electronics 5 and the fluid F flowing through the tubular body 22 can be improved. 

1. A fluid pump for delivering a fluid of a cooling system, comprising: a pump housing surrounding a pump housing interior on which a fluid inlet for introducing the fluid into the pump housing interior and a fluid outlet for discharging the fluid out of the pump housing interior are disposed, a delivery unit arranged in the pump housing interior for driving the fluid introduced into the pump housing interior, an electric motor arranged in the pump housing interior for driving the delivery unit, and a control device arranged outside the pump housing and comprising power electronics, wherein the control device is electrically connected to the electric motor for controlling the electric motor.
 2. The fluid pump according to claim 1, wherein the control device is arranged spaced apart from the pump housing and electrically connected to the electric motor via an electrical connection.
 3. The fluid pump according to claim 1, wherein the control device includes a housing structured separately from the pump housing, and wherein the housing of the control device surrounds a housing interior in which the power electronics is arranged.
 4. The fluid pump according to claim 3, wherein the housing of the control device is arranged spaced apart from the pump housing.
 5. The fluid pump according to claim 3, wherein a housing material of the housing of the control device is a metal at least in one region.
 6. The fluid pump according to claim 3, wherein an electrical feedthrough is provided on each of the pump housing and on the housing of the control device, and wherein an electrical connection is fed through each electrical feedthrough between the electric motor and the power electronics.
 7. The fluid pump according to claim 6, wherein the electrical connection includes at least two electrical supply lines for electrically energising the electric motor.
 8. The fluid pump according to claim 6, wherein the electrical connection includes an electrical shield.
 9. The fluid pump according to claim 1, wherein the pump housing is a one-piece housing.
 10. The fluid pump according to claim 9, wherein the one-piece pump housing is structured out of at least two housing parts which that are each non-detachably connected to one another via a firmly bonded connection.
 11. The fluid pump according to claim 9, wherein the one-piece pump housing includes a pump housing flange for mounting the pump housing to an external cooling system, and wherein pump housing flange radially projects from a circumferential wall of the pump housing and is integrally formed on the circumferential wall.
 12. The fluid pump according to claim 1, wherein a material of the pump housing includes a plastic.
 13. A cooling system, comprising: a fluid path that can be flowed through by a fluid, a fluid pump arranged in the fluid path for delivering the fluid in the fluid path, the fluid pump including: a pump housing surrounding a pump housing interior on which a fluid inlet for introducing the fluid into the pump housing interior and a fluid outlet for discharging the fluid out of the pump housing interior are disposed, a delivery unit arranged in the pump housing interior for driving the fluid introduced into the pump housing interior, an electric motor arranged in the pump housing interior for driving the delivery unit, a control device arranged outside the pump housing and comprising power electronics, wherein the control device is electrically connected to the electric motor for controlling the electric motor, and wherein the control device of the fluid pump is arranged spaced apart from the pump housing and is thermally coupled to the fluid path, so that the waste heat generated by the control device during operation is passed on to the fluid delivered through the fluid path.
 14. The cooling system according to claim 13, wherein the fluid path is delimited by a tubular body, on which the control device is arranged.
 15. The cooling system according to claim 13, further comprising a modular flange, on which the fluid pump is fastened.
 16. The cooling system according to claim 15, wherein the pump housing includes a pump housing flange projecting radially from a circumferential wall of the pump housing, and wherein the pump housing flange is coupled to the modular flange for mounting the fluid pump.
 17. The cooling system according to claim 13, wherein the control device includes a housing structured separately from the pump housing, and wherein the housing of the control device surrounds a housing interior in which the power electronics is arranged.
 18. The cooling system according to claim 17, wherein the pump housing and the housing of the control device each have an electrical feedthrough, and wherein an electrical connection between the electric motor and the power electronics is fed through the electrical feedthrough of the pump housing and the housing of the control device.
 19. The cooling system according to claim 18, wherein the electrical connection includes an electrical shielding line.
 20. The cooling system according to claim 18, wherein the electrical connection includes at least two electrical supply lines for electrically energising a stator of the electric motor. 